Field
The present embodiments relate to batteries for portable electronic devices. More specifically, the present embodiments relate to techniques for using reference electrodes to manage the design and use of lithium-polymer batteries with the portable electronic devices.
Related Art
Portable electronic devices, such as laptop computers, portable media players, and/or mobile phones, typically operate using a rechargeable battery. Furthermore, designs for such batteries often include battery packs that contain battery cells connected together in various series and parallel configurations.
During operation, the battery's capacity may diminish over time from use, age, lack of maintenance, damage, heat, and/or manufacturing defects. For example, oxidation of electrolyte, degradation of cathode and anode material, and/or lithium plating on the anode surface of a battery may be caused by repeated and/or inefficient (e.g., constant-current) charging of the battery, which in turn may cause a gradual reduction in the battery's capacity. As the battery continues to age and degrade, the capacity's rate of reduction may increase. Once the battery reaches 80% of initial capacity, the battery's useful life may be finished.
Subsequent use of a battery beyond the battery's end-of-life may cause swelling of the battery's cells and continued lithium plating on the battery's anode surface while providing little power to the portable electronic device. Moreover, conventional battery-monitoring mechanisms may not include functionality to manage such swelling and/or lithium plating. As a result, a user of the portable electronic device may not be aware of the battery's degraded state until the battery fails and/or the device is damaged, which can possibly involve a fire, an explosion, and/or an electrical short.
Hence, what is needed is a mechanism for managing and mitigating degradation, loss of capacity, and/or faults in batteries for portable electronic devices.